This mount fits most Shield RMSc cut pistols. This adapter plate mounts directly to the pistol using the fasteners provided with the mount. The Trijicon RMRcc is then mounted to this adapter using the Trijicon supplied fasteners. Professional Installation Recommended. Fits Glock 43X MOS and 48 MOS; all Smith & Wesson M&P Shield C.O.R.E models, Springfield Hellcat OSP; Springfield XD-S Optics Ready; Ruger Max-9 Optics Ready; Mossberg MC2 SC; and SCCY CPX1 and CPX2 Optics Ready.